Patent GB-525647-A (GB)
Title: Improvements in or relating to control apparatus for a clutch
IPC: F16D43/12
Filed: 1939-02-24
Abstract: 525,647. Operating clutches. BORG-WARNER CORPORATION. Feb. 24, 1939, No. 6201. Convention date, March 3, 1938. [Class 80 (ii)] The connection between the actuating fork 34, fixed on a shaft 33, of a friction clutch and the control pedal 25 can be changed, by manually-operated means, from one condition, in which depression of the pedal rocks the fork in one direction to disengage the clutch, into a second condition in which depression of the pedal rocks the fork in the other. direction to engage the clutch. In the centrifugal clutch shown, engagement is normally effected, against the action of retractor springs 14, by the centrifugally-induced outward movement, between the pressure plate 10 and the inclined surfaces of members 16 secured to the cover plate 2, of rollers 12, each of which is connected by a link 15 to a sleeve 17 provided with collars 18 and 19 between which is arranged a collar 20 connected to the fork 34, the arrangement being such that the clutch, when fully engaged, cannot disengage automatically upon reduction of speed. The plate 10 is connected to the cover 2 by spring plates 11, the cover being secured to the driving flywheel 1 by screws 3 with interposed springs 4 which take the reaction. In the form shown in Fig. 2, the pedal 25 is journalled on a stud 26, on which are also journalled two arms 27 and 29 connected respectively by links 28 and 30 to opposed arms 31 and 32 fixed to the shaft 33. A latch 35 pivoted on the pedal 25 is movable by manually-operable Bowden mechanism 36, when the pedal is in released position, from a normal position (as shown) in which it engages a notch 40 in the arm 29, so as to connect the pedal to that arm, to a position in which it engages a notch 39 in the arm 27, so as to connect the pedal to the latter arm. With the pedal released, the collar 20 does not contact with either of the collars 18 and 19, whether the clutch is engaged or disengaged. Thus, with the latch in the normal position and the clutch engaged, depression of the pedal (as shown) causes the collar 20 to move to the right to engage the collar 19, whereby the sleeve 17 is moved to disengage the clutch. On moving the latch into engagement with the arm 27 and then depressing the pedal, the collar 20 moves to the left to engage the collar 18 and move the sleeve 17 to produce clutch engagement if the clutch is not already engaged centrifugally. In the form shown in Fig. 8, the pedal 25 is connected by a tension link 139 to an arm 150 loose on the shaft 33. Opposed arms 142 and 143, carrying adjustable abutment screws 145 and 146, are fixed on the shaft 33. A lever 152, pivoted on a fixed pin 53 and having an elongated slot engaged by a pin 15i on the arm 150, is movable by manuallyoperable Bowden mechanism 58 from the normal inclined position shown, in which the screw 146 co-operates with an abutment 62 on the arm 150, to an oppositely-inclined position in which the screw 145 co-operates with the abutment 62, the lever 152 being maintained in either position by a throw-over spring 55. With the lever 152 in the first position, depression of the pedal causes clockwise movement of the fork and thus disengagement of the clutch, while, with the lever in the second position, depression of the pedal causes anticlockwise movement of the fork and thus engagement of the clutch. A slightly-modified arrangement, wherein the tension link 139 is replaced by a compression link, is also described.